FIGURE 2.2 Species on the brink. Humans have saved some species from the brink of extinction, such as (a) the American bison and (b) the peregrine falcon. Other species, such as the (c) snow leopard and (d) the West Indian manatee, continue to decline.
(a: Richard A. McMillin/Shutterstock; b: Jim Zipp/Science Source; c: AlanCarey/Science Source; d: Douglas Faulkner/Science Source)